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1.
Water Sci Technol ; 89(11): 2991-3006, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38877626

RESUMO

Recent decades have seen a shortage of water, which has led scientists to concentrate on solar desalination technologies. The present study examines the solar water desalination system with inclined steps, while considering various phase change materials (PCMs). The findings suggest that the incorporation of PCM generally enhances the productivity of the solar desalination system. Additionally, the combination of nanoparticles has been used to PCM, which is a popular technique utilized nowadays to improve the efficiency of these systems. The current investigation involves the transient modeling of a solar water desalination system, utilizing energy conservation equations. The equations were solved using the Runge-Kutta technique of the ODE23s order. The temperatures of the salt water, the absorbent plate of the glass cover, and the PCM were calculated at each time. Without a phase changer, the rate at which fresh water is produced is around 5.15 kg/m2·h. The corresponding mass flow rates of paraffin, n-PCM I, n-PCM III, n-PCM II, and stearic acid are 22.9, 28.9, 5.9, 11.9, and 73 kg/m2·h. PCMs, with the exception of stearic acid, exhibit similar energy efficiency up to an ambient temperature of around 29°. However, at temperatures over 29°, n-PCM II outperforms other PCM.


Assuntos
Nanoestruturas , Luz Solar , Purificação da Água , Purificação da Água/métodos , Purificação da Água/instrumentação , Nanoestruturas/química , Temperatura
2.
J Mol Graph Model ; 129: 108745, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38442441

RESUMO

With the goal of developing a high-performance organic solar cell, nine molecules of A2-D-A1-D-A2 type are originated in the current investigation. The optoelectronic properties of all the proposed compounds are examined by employing the DFT approach and the B3LYP functional with a 6-31G (d, p) basis set. By substituting the terminal moieties of reference molecule with newly proposed acceptor groups, several optoelectronic and photovoltaic characteristics of OSCs have been studied, which are improved to a significant level when compared with reference molecule, i.e., absorption properties, excitation energy, exciton binding energy, band gap, oscillator strength, electrostatic potential, light-harvesting efficiency, transition density matrix, open-circuit voltage, fill factor, density of states and interaction coefficient. All the newly developed molecules (P1-P9) have improved λmax, small band gap, high oscillator strengths, and low excitation energies compared to the reference molecule. Among all the studied compounds, P9 possesses the least binding energy (0.24 eV), P8 has high interaction coefficient (0.70842), P3 has improved electron mobility due to the least electron reorganization energy (λe = 0.009182 eV), and P5 illustrates high light-harvesting efficiency (0.7180). P8 and P9 displayed better Voc results (1.32 eV and 1.33 eV, respectively) and FF (0.9049 and 0.9055, respectively). Likewise, the phenomenon of charge transfer in the PTB7-Th/P1 blend seems to be a marvelous attempt to introduce them in organic photovoltaics. Consequently, the outcomes of these parameters demonstrate that adding new acceptors to reference molecule is substantial for the breakthrough development of organic solar cells (OSCs).


Assuntos
Elétrons , Osteosclerose , Pirróis , Humanos , Cetonas
3.
Int J Rheum Dis ; 26(7): 1227-1234, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37309305

RESUMO

COVID-19 vaccines approved by the Food and Drug Administration have been studied mainly in healthy individuals and there is limited information on their immunogenicity in patients with autoimmune diseases. Therefore, the current systematic review and meta-analysis study, aimed to comprehensively investigate the immunogenicity of these vaccines in patients with autoimmune inflammatory rheumatoid diseases (AIRDs). A comprehensive literature search was performed on various databases, including Google Scholar, PubMed, Web of Science, EMBASE, and Cochrane Library, to select cohort and randomized clinical trial (RCT) studies up to January 2022. Also, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist protocol and the I2 statistic were used for quality assessment and heterogeneity tests of the selected studies. Fixed and random-effects models were estimated based on the heterogeneity tests, and pooled data were determined as the ratio of mean (ROM) with a 95% confidence interval (CI). As a result, we found that vaccines can cause favorable immunogenicity and antibody response in vaccinated AIRD patients; however, older age and the concomitant consumption of conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs) and biologic DMARDs (bDMARDs) could significantly reduce the vaccine immunogenicity. Consequently, our findings revealed significant humoral responses (seropositive) in AIRD patients following the administration of COVID-19 vaccines.


Assuntos
Antirreumáticos , Artrite Reumatoide , Doenças Autoimunes , Vacinas contra COVID-19 , COVID-19 , Doenças Reumáticas , Adulto , Humanos , Antirreumáticos/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/tratamento farmacológico , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Doenças Reumáticas/diagnóstico , Doenças Reumáticas/tratamento farmacológico
4.
Transpl Immunol ; 79: 101858, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37236514

RESUMO

COVID-19 vaccines exhibit high levels of immunogenicity in the overall population. Data on the effects of immunomodulators on the consequences of COVID-19 in patients with Immune-mediated inflammatory diseases (IMIDs) remains scarce. This systematic review aimed to evaluate the immune responses to the COVID-19 vaccines in IMID patients receiving methotrexate (MTX) compared to healthy individuals. A comprehensive literature search was carried out using electronic databases such as PubMed, Web of Science, Scopus, Google Scholar, and Embase up to August 2022 to identify eligible RCTs evaluating the effect of MTX on immune responses in patients with COVID-19. The PRISMA checklist protocol was applied for the quality assessment of the selected trials. Our findings demonstrated that MTX lowered the responses of T cells and antibodies in IMID patients compared to healthy controls. We also discovered that young age (<60 years) was the main parameter influencing the antibody response after vaccination, while MTX had little effect. Following vaccination, MTX-hold and age were considered the main factors influencing the antibody response. In patients older than 60 years of age, the time point of 10 days of MTX discontinuation was critical to boosting the humoral response to anti-SARS-CoV-2 IgG. Because many IMID patients did not have adequate humoral and cellular responses, our findings highlighted the importance of second or booster doses of vaccine and temporary MTX discontinuation. As a result, it implies that individuals with IMIDs should be subjected to more research, particularly humoral and cellular immunity efficiency trials after COVID-19 vaccination, until credible information is achieved.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Recém-Nascido , Pessoa de Meia-Idade , Vacinas contra COVID-19/uso terapêutico , Metotrexato/uso terapêutico , Agentes de Imunomodulação , Imunoglobulina G , Anticorpos Antivirais , Imunidade Celular
5.
Med Oncol ; 40(5): 155, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37083979

RESUMO

Nowadays, one of the main challenges clinicians face is malignancies. Through the progression of technology in recent years, tumor nature and tumor microenvironment (TME) can be better understood. Because of immune system involvement in tumorigenesis and immune cell dysfunction in the tumor microenvironment, clinicians encounter significant challenges in patient treatment and normal function recovery. The tumor microenvironment can stop the development of tumor antigen-specific helper and cytotoxic T cells in the tumor invasion process. Tumors stimulate the production of proinflammatory and immunosuppressive factors and cells that inhibit immune responses. Despite the more successful outcomes, the current cancer therapeutic approaches, including surgery, chemotherapy, and radiotherapy, have not been effective enough for tumor eradication. Hence, developing new treatment strategies such as monoclonal antibodies, adaptive cell therapies, cancer vaccines, checkpoint inhibitors, and cytokines helps improve cancer treatment. Among adoptive cell therapies, the interaction between the immune system and malignancies and using molecular biology led to the development of chimeric antigen receptor (CAR) T cell therapy. CAR-modified immune cells are one of the modern cancer therapeutic methods with encouraging outcomes in most hematological and solid cancers. The current study aimed to discuss the structure, formation, subtypes, and application of CAR immune cells in hematologic malignancies and solid tumors.


Assuntos
Imunoterapia , Neoplasias , Humanos , Imunoterapia/métodos , Neoplasias/terapia , Imunoterapia Adotiva/métodos , Linfócitos T Citotóxicos , Antígenos de Neoplasias , Microambiente Tumoral
6.
J Cancer Res Clin Oncol ; 149(10): 7945-7968, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36905421

RESUMO

CXC chemokine receptor type 4 (CXCR4) is a member of the G protein-coupled receptors (GPCRs) superfamily and is specific for CXC chemokine ligand 12 (CXCL12, also known as SDF-1), which makes CXCL12/CXCR4 axis. CXCR4 interacts with its ligand, triggering downstream signaling pathways that influence cell proliferation chemotaxis, migration, and gene expression. The interaction also regulates physiological processes, including hematopoiesis, organogenesis, and tissue repair. Multiple evidence revealed that CXCL12/CXCR4 axis is implicated in several pathways involved in carcinogenesis and plays a key role in tumor growth, survival, angiogenesis, metastasis, and therapeutic resistance. Several CXCR4-targeting compounds have been discovered and used for preclinical and clinical cancer therapy, most of which have shown promising anti-tumor activity. In this review, we summarized the physiological signaling of the CXCL12/CXCR4 axis and described the role of this axis in tumor progression, and focused on the potential therapeutic options and strategies to block CXCR4.


Assuntos
Neoplasias , Receptores CXCR4 , Humanos , Receptores CXCR4/genética , Ligantes , Quimiocina CXCL12/genética , Neoplasias/genética , Transdução de Sinais , Carcinogênese
7.
Cancer Cell Int ; 22(1): 365, 2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36419058

RESUMO

In recent decades, the advent of immune-based therapies, most notably Chimeric antigen receptor (CAR)-T cell therapy has revolutionized cancer treatment. The promising results of numerous studies indicate that CAR-T cell therapy has had a remarkable ability and successful performance in treating blood cancers. However, the heterogeneity and immunosuppressive tumor microenvironment (TME) of solid tumors have challenged the effectiveness of these anti-tumor fighters by creating various barriers. Despite the promising results of this therapeutic approach, including tumor degradation and patient improvement, there are some concerns about the efficacy and safety of the widespread use of this treatment in the clinic. Complex and suppressing tumor microenvironment, tumor antigen heterogeneity, the difficulty of cell trafficking, CAR-T cell exhaustion, and reduced cytotoxicity in the tumor site limit the applicability of CAR-T cell therapy and highlights the requiring to improve the performance of this treatment. With this in mind, in the last decade, many efforts have been made to use other treatments for cancer in combination with tuberculosis to increase the effectiveness of CAR-T cell therapy, especially in solid tumors. The combination therapy results have promising consequences for tumor regression and better cancer control compared to single therapies. Therefore, this study aimed to comprehensively discuss different cancer treatment methods in combination with CAR-T cell therapy and their therapeutic outcomes, which can be a helpful perspective for improving cancer treatment in the near future.

8.
Nat Prod Res ; 36(20): 5268-5276, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34030539

RESUMO

Three new derivatives of tetrahydrocurcumin 6, 7 and 9 have been prepared as potent antitumor agents using copper(II)-catalyzed 'click chemistry'. Their structures were identified using 1H-NMR, 13C-NMR and HRMS techniques. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay has been carried out to investigate the in vitro cytotoxicity against human cervical carcinoma (HeLa), human lung adenocarcinoma (A549), human hepatoma carcinoma (HepG2) and human colon carcinoma (HCT-116). Compound 6 has showed significant inhibitory activity against HCT-116 cell line with an IC50 value of 17.86 µM compared to tetrahydrocurcumin (50.96 µM) and positive control etoposide (19.48 µM) while showed no inhibitory activity against NCM460 cell line. Compounds 7 showed moderate inhibitory activity compared to tetrahydrocurcumin and etoposide while compound 9 showed no obvious inhibitory activity. The results suggested further structure modifications of tetrahydrocurcumin to improve its anticancer activity.[Formula: see text].


Assuntos
Antineoplásicos , Carcinoma , Antineoplásicos/química , Linhagem Celular Tumoral , Cobre , Curcumina/análogos & derivados , Ensaios de Seleção de Medicamentos Antitumorais , Etoposídeo , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
9.
JPEN J Parenter Enteral Nutr ; 27(1): 58-64, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12549600

RESUMO

BACKGROUND: Particle size of IV lipid emulsions affects the catabolism of long-chain triglyceride (LCT) emulsions, but little is known about its effect on the catabolism of medium-chain triglyceride (MCT)- and fish oil (FO)-containing emulsions. METHODS: Large (VLDL size), intermediate, and small (IDL size) emulsions with different triglyceride (TG) compositions were labeled with [3H]cholesteryl oleoyl ether: LCT (triolein 100%), MCT:LCT (trioctanoin:triolein 50%:50%), MCT:LCT:FO (trioctanoin:triolein:triDHA 50%:40%:10%), and FO (triDHA 100%). Emulsions (0.4 mg TG/mouse) were injected into C57BL/6J mice, and blood clearance and tissue uptake of emulsion particles were determined. RESULTS: Large emulsion particles had 2- to 3-fold faster fractional catabolic rates (FCR) compared with small particles with the same TG content. There was 1.5- to 2.0-fold higher FCR of large FO-containing emulsions (FO and MCT:LCT:FO) compared with large LCT and MCT:LCT emulsions, whereas effects of FO on FCR in small emulsions were not observed. Large FO-containing emulsions were taken up more by adipose tissue compared with small particles with concomitant decreases in hepatic uptake. Preinjection of heparin reduced heart and adipose uptakes of FO and MCT:LCT:FO emulsions with increased uptake by liver, suggesting a role of lipoprotein lipase in catabolism of FO-containing emulsions. CONCLUSIONS: In a mouse model, FO addition to large emulsions increased blood clearance and changed organ delivery. In contrast, there was no or little effect when particle size became smaller. We hypothesize that in humans, FO addition to lipid emulsions can help target emulsion delivery to certain extrahepatic tissues, a factor that may be of use for delivering specific fatty acids, or even drugs, to specific organs.


Assuntos
Emulsões Gordurosas Intravenosas/metabolismo , Óleos de Peixe/administração & dosagem , Óleos de Peixe/metabolismo , Triglicerídeos/administração & dosagem , Triglicerídeos/metabolismo , Análise de Variância , Animais , Anticoagulantes/farmacologia , Cromatografia , Feminino , Heparina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Tamanho da Partícula , Fatores de Tempo
10.
Atherosclerosis ; 166(2): 243-51, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12535736

RESUMO

Lipoprotein lipase (LPL) is central to triacylglycerol (TG) metabolism, having both hydrolytic and bridging functions. The common LPL gene variant D9N is associated with raised TG, reduced HDL-cholesterol concentrations and increased risk of coronary artery disease (CAD). To investigate the functional basis for the phenotype in N9 carriers, CHO K1 cells were stably transfected with wild type (D9) or mutant (N9) LPL cDNA. LPL RNA expression levels, monomer-to-dimer ratios, and dimer specific activities were similar in D9 and N9 cells. Significantly enhanced binding (4.6-fold) and internalisation (2.6-fold) of 125I-LDL by N9 compared with D9 cells was eradicated by pre-treatment with either heparin or heparinase, confirming involvement of LPL and cell surface proteoglycans. N9 cells bound and internalised 3.8- and 4.4-fold more oxidised 125I-LDL, respectively, than D9 cells (both P<0.0001). Binding of monocytes was 7-fold greater to plates coated with purified LPL-N9 dimer compared with LPL-D9 (P<=0.005). Thus once on the cell surface, LPL-N9 enhances bridging, as assessed both by LDL binding and internalisation, and monocyte adhesion. This augmented LPL-N9 bridging provides a mechanism for the reported increased CAD risk in N9 carriers.


Assuntos
Doença da Artéria Coronariana/genética , Heterozigoto , Lipase Lipoproteica/genética , Triglicerídeos/genética , Sequência de Bases , Adesão Celular , Células Cultivadas , Doença da Artéria Coronariana/fisiopatologia , Predisposição Genética para Doença , Humanos , Lipase Lipoproteica/metabolismo , Dados de Sequência Molecular , Monócitos/fisiologia , Probabilidade , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Sensibilidade e Especificidade , Triglicerídeos/metabolismo
11.
Arterioscler Thromb Vasc Biol ; 22(12): 2080-5, 2002 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-12482838

RESUMO

OBJECTIVE: Liver-derived apolipoprotein E (apoE) decreases atherosclerosis without altering the circulating concentrations of plasma lipoproteins. We evaluated the effects of apoE and lipoprotein lipase (LpL) on the interactions of triglyceride-rich particles (TGRPs) in the arterial wall. METHODS AND RESULTS: Quantitative fluorescence microscopy was used to study the interactions of TGRPs (25- to 35-nm diameter) in the arterial wall. Carotid arteries were harvested from rats, placed in a perfusion chamber, and perfused with fluorescently labeled TGRPs. In the absence of apoE or LpL, 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine-TGRP (100 microg neutral lipid/mL) was poorly retained in the arterial wall. The addition of either apoE (10 microg/mL) or LpL (10 microg/mL) increased TGRP accumulation 220% and 100%, respectively. This effect was attenuated by heparin (10.0 IU/mL). Histological analyses of cross sections from these vessels demonstrate that in the absence of apoE or LpL, there is deep penetration of lipid into the arterial wall. With the addition of either apoE or LpL, arterial wall penetration of TGRP is blocked. CONCLUSIONS: These results demonstrate that although apoE and LpL increase arterial wall accumulation of TGRPs, these proteins also reduce the penetration of TGRPs into the arterial wall. We postulate that this may represent a novel antiatherogenic property of apoE and LpL.


Assuntos
Apolipoproteínas E/fisiologia , Lipase Lipoproteica/fisiologia , Lipoproteínas/fisiologia , Triglicerídeos/fisiologia , Animais , Carbocianinas/metabolismo , Artérias Carótidas/química , Artérias Carótidas/enzimologia , Cultura em Câmaras de Difusão , Corantes Fluorescentes/metabolismo , Proteoglicanas de Heparan Sulfato/fisiologia , Técnicas In Vitro , Masculino , Microscopia de Fluorescência , Perfusão , Ligação Proteica/fisiologia , Ratos , Ratos Sprague-Dawley
12.
Biochemistry ; 41(9): 3119-27, 2002 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-11863451

RESUMO

Omega-3-rich (n-3) triglycerides (TG) are increasingly recognized as having modulating roles in many physiological and pathological conditions. We questioned whether the catabolism of lipid emulsions would be changed after enrichment with fish oil (n-3) TG as compared to enrichment with omega-6-rich soy oil (n-6) TG. Phospholipid-stabilized emulsions of n-3 TG and n-6 TG were labeled with [(3)H]cholesteryl oleoyl ether and administered by bolus injection to wild-type (WT) mice, mice lacking the low-density lipoprotein receptor (LDL-R) (LDL-R -/-), and apolipoprotein E (apoE) knockout mice (apoE -/-). The effects of exogenous apoE, heparin, Triton WR 1339, and lactoferrin on catabolism of emulsions were also assayed. n-3 TG emulsions were cleared faster from blood and had different extrahepatic tissue targeting compared to n-6 TG emulsions. In apoE -/- and LDL-R -/- mice, blood clearance of n-6 TG emulsions slowed with decreased liver uptake, but no changes were observed in n-3 TG emulsion clearance and tissue uptake compared to WT mice. In WT mice, addition of exogenous apoE to the emulsion increased liver uptake of n-6 TG emulsions but had no impact on n-3 TG emulsions. Pre-injection of heparin increased and Triton WR 1339 and lactoferrin decreased blood clearance of n-6 TG emulsions with little or no effect on n-3 TG emulsions. Liver uptake of n-6 TG emulsions increased after heparin injection and decreased after Triton WR 1339 injection, but uptake of n-3 TG emulsions was not changed. These data show that the catabolism of n-3 TG emulsions and the catabolism of n-6 TG emulsions occur via very different mechanisms. Removal of chylomicron-sized n-6 TG emulsions is modulated by lipoprotein lipase (LPL), apoE, LDL-R, and lactoferrin-sensitive pathways. In contrast, clearance of chylomicron-sized n-3 TG emulsions relies on LPL to a very minor extent and is independent of apoE, LDL-R, and lactoferrin-sensitive pathways.


Assuntos
Emulsões Gordurosas Intravenosas/farmacocinética , Óleos de Peixe/farmacocinética , Óleo de Soja/farmacocinética , Triglicerídeos/farmacocinética , Animais , Apolipoproteínas E/metabolismo , Feminino , Fibroblastos/metabolismo , Lactoferrina/metabolismo , Lipase Lipoproteica/metabolismo , Taxa de Depuração Metabólica , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Receptores de LDL/metabolismo , Distribuição Tecidual , Triglicerídeos/química
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